/* jsx ctrl+m*/
import React, { Component } from 'react';
import './css/index.css'
class App extends Component {
  constructor(props){
    /* 组件的构造函数中一定要加上super */
    super(props);
    this.state = {
      msg:"hello react"
    }
  }
  render() {
    return (
      /* html的class写成className */
      <div className="item">
         {this.state.msg}
      </div>
    );
  }
}
export default App;


